Comments

1. TooMuchRice MakesMeSick
   29 Apr 2007 at 05:13
   I am getting the same exact error message.
   Is there any fix? The code does not work
   
   
   Error is
   
   "Index was outside the bounds of the array."
   
   
   on line
   
   
   bytes[3] =  tagSize[3]             | ((tagSize[2] & 1) << 7) ;
   
   
   
   
   
   
   
   
   
   
   
   
2. Pedro Rodriguez
   11 Nov 2006 at 01:06

   Im interested in your VB version

   Sheratore9@hotmail.com

   I'M having Problems reading APIC , and i think i have problems with SynchSafe Integers

   Can AnyOne tell me if this is true

   00000011 00000001 =

   759 Normal?

   385 SynchSafe?

   and if i multiply the 2nd Byte * 128 an 3rd byte * 16384 and so on i get the values too?

   Sorry for my English

3. John Pavlik
   08 Aug 2006 at 15:17

   Apparently synchsafe integers are not used in 2.2 or 2.3 - they were added in 2.4.

   ulong GetFrameSize(char[] tagSize, int version)
   {
    int shift = 8;
    int mask = 0xff;
    if (version == 4)
    {
     // The ID3v2 tag size is encoded with four bytes
     // where the most significant bit (bit 7)
     // is set to zero in every byte,
     // making a total of 28 bits.
     // The zeroed bits are ignored
     shift = 7;
     mask = 0x7f;
    }
    ulong newSize = 0;
    for (int i=0; i < tagSize.Length; i++)
    {
     newSize <<= shift;
     newSize |= (ulong)tagSize[i] & mask;
    }
    return newSize;
   }
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   

   public id3v2Frame ReadFrame (BinaryReader br, int version)
   {
    .... bunch of stuff
    if (version == 2)
    {
     // only have 3 bytes for size ;
     tagSize = br.ReadChars(3);    // I use this to read the bytes in from the file
     newSize = GetFrameSize(tagSize,version);
    }
    else if (version == 3 || version == 4)
    {
     // version  2.4
     tagSize = br.ReadChars(4);    // I use this to read the bytes in from the file
     bytes = new int[4];      // for bit shifting
     newSize = GetFrameSize(tagSize,version);
    }
    f1.frameSize = newSize;
    ....
   }
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   

   Also, there are frames which can be added more than once (PRIV for example) which Hashtable.Add causes an exception.  Ideally you should be able to add them with some other hash but I just catch and ignore the exception.

   Hope this helps other people.

    

   John

4. John Pavlik
   07 Aug 2006 at 22:37

   Pretty nice.  You could simplify the synchsafe reading though.

   ulong MakeSynchsafeInt(char[] tagSize)
   {
    const int shift = 7; 
    const int mask = 0x7f;  
    ulong newSize = 0;
    for (int i=0; i < tagSize.Length; i++)
    {
     newSize <<= shift;
     newSize |= (ulong)tagSize[i] & mask;
    }
    return newSize;
   }
   
   
   
   
   
   
   
   
   
   
   
   Funny thing though, seems that a lot of programs don't write the frame sizes in this format.  I was trying to extend to read the APIC tag and realized I only got half a picture.  Anyone else seen this?
   

   if(this.framesHash.Contains("APIC"))
   {
    StringBuilder mimetype = new StringBuilder();
    StringBuilder description = new StringBuilder();
    byte [] bytes = ((id3v2Frame)this.framesHash["APIC"]).frameContents;
    byte textEncoding;
    byte pictureType;
   
   
   
   
   
   

    int i = 0;
    if (i < bytes.Length)
     textEncoding = bytes[i++];
    while (i < bytes.Length)
    {
     mimetype.Append(System.Convert.ToChar(bytes[i++]));
     if (bytes[i-1] == 0)
      break;
    }
    if (i < bytes.Length)
     pictureType = bytes[i++];
    while (i < bytes.Length)
    {
     description.Append(System.Convert.ToChar(bytes[i++]));
     if (bytes[i-1] == 0)
      break;
     if (bytes[i-1] == 0xff)
     {
      i--;
      break;
     }
    }
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   

    if (i < bytes.Length)
    {
     MemoryStream stream = new MemoryStream(bytes,i,bytes.Length - i);
     albumCover = Image.FromStream(stream);
    }
   
   
   
   

   }

    

5. Dave Dolson
   30 Jun 2006 at 14:32

   If you can provide the code I'd like to see it.

    

   Thanks in advance

   Dave Dolson

   dadolson@hotmail.com

6. Ian Robertson
   12 Feb 2006 at 00:05

   After downloading the C# classes, I converted them to VB, using online conversion tools. After sorting out a few conversion errors, I managed to get the classes working in VB.
   

   
   After some extensive testing, I have started to spot and resolve some basic logic errors present in the original code. (Mainly trying to use objects which arent instantiated). The original classes were not particularly well thought out - for each operation (many of them), the code would create a new filestream from the underlying file. The file was being read 5-6 times. I've fixed that! It now passes round a reference to the FileStream instead of recreating it each time...that should save the live of a few HDDs ;)
   

   
   I am using the classes to scan through 10,000+ files, and after some effort, it manages to process all of them. These classes use a lot of memory, so I am going to try and resolve that, so that all 10,000+ files can be processed in one batch. (I only have 1/2GB RAM, and it takes it all at present!). The classes were poorly written. I mean everything was "public", there were no properties!
   

   
   If anyone wants what Ive done so far, give me a holla, and I will sort you out. :D

7. raghu_429
   10 Sep 2005 at 00:41

   Hi,
   This is the exact code I was looking for, but I'm newbie and have no C# knowledge, I'm a C guy working on embedded systems. If you could help me in this regard, I shall be obliged. Is there any documentation for your code or do you have any C version of this code?
   I'm interested in reading the basic stuff like artist, album, and genre (nothing else), from ID3v1 and ID3v2 tags, please guide me I'm running out of time.
   

8. Tass99
   17 Jul 2005 at 22:05
   
   Hi
   
   This is exactly what I've been looking for!  Thanks!
   
   I'm a little stuck though.  When calling the read method of teh ID3V2 class, I get an IndexOutOfRange error.  It's from the ReadFrame method of the ID3v2Frame class (line 105) -  Additional information: Index was outside the bounds of the array.
   
   This is on the line that calls  :
   
   bytes[3] =  tagSize[2]             | ((tagSize[1] & 1) << 7) ;
   
   
   Any ideas?
   
   Thanks
9. Developer Fusion Bot
   01 Jan 1999 at 00:00

   This thread is for discussions of Read MP3 Tag Information (ID3v1 and ID3v2).